The present invention relates in general to semi-conductor manufacturing technologies and in particular to methods and apparatus of optimizing a set of operations in a semi-conductor capital equipment processing system.
Semi-conductor fabrication facilities often cost billions of dollars to design and operate. Optimizing throughput and decreasing costs are therefore critical for profitability. Capital equipment processing systems within these facilities, however, often require significant human manual intervention creating the potential for process variances or even outright operation mistakes.
Most semi-conductor capital equipment processing systems are normally controlled by sophisticated computers comprising operating software programs, wherein users via a interface are provided the ability to send requests to the equipment and receive output information from the equipment. These procedure steps for the most part are executed manually. In a typical operating environment, the user manually configures parameters for the manufacturing process (e.g., voltage, gas flow mix, gas flow rate, pressure, etc.) and then manually initiates start execution. The processing system examines its state by either evaluating signals from one or more sensing devices (e.g., position encoders, temperature and pressure sensors, flow rate indicators, etc.) or by requesting that the operator input information (e.g. the results of spectra optical emission, gas proportion mix, etc.). Test product is initially run through the system, to insure that the process is within acceptable parameters, after which the production run is started. During this process, the operator is usually expected to follow printed procedures and physically write down system measurements at appropriate time.
However, because of differences in training, experience, or attitude, different operators can implement the same test differently on the same machine. Furthermore, information entered in the process data notebooks may be incomplete or incorrect, presenting problems for process engineers who are tasked to insure that the fabrication process is optimally configured and manufacturing yields are maintained at an acceptable level.
Process variance is further compounded when multiple versions of the same processing system are concurrently used in the manufacture of the same product. Since an otherwise identical piece of fabrication equipment may be installed at a different time, or is used to a different degree, its maintenance cycle does not necessarily match that of the others, potentially causing chamber-to-chamber process variation.
Furthermore, there is often a need to safely and quickly modify the operation of a processing system at the customer site. In general, changes in semi-conductor fabrication equipment procedures are often difficult to implement, especially in the case of multiple equipment units. This lack of process flexibility can create substantial inefficiency and hence significantly increase production costs. For example, a customer may want the processing equipment to perform a new testing procedure because of some newly discovered process variance. In order to implement this new procedure, the vendor must first create or modify an existing written procedure and send a field engineer to the customer site to perform training, then monitor for changes in tool performance for a period of time to insure proper functionality. This process can take several weeks, potentially costing several hundreds of thousands of dollars.
In view of the foregoing, there is desired an architecture for a general purpose programmable semi-conductor processing system.